loser

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. One that fails to win: the losers of the game.
2. n. One who takes loss in a specified way: a graceful loser; a poor loser.
3. n. One that fails consistently, especially a person with bad luck or poor skills: "losers at home seeking wealth and glory in undeveloped countries” ( Arthur M. Schlesinger, Jr.)
4. n. One that is bad in quality: That book is a real loser.

Century Dictionary and Cyclopedia

1. n. One who loses, or is subjected to loss; one who fails to win, gain, or keep.

Wiktionary

1. n. A person who fails to win.
2. n. Someone who loses in a specified manner.
3. n. Someone with bad luck or poor skills who consistently loses.
4. n. Something of poor quality.
5. n. A person of unhappy circumstances.
6. n. A contemptible or unfashionable person.
7. n. Someone that has lost weight. (a recent term, originally from Kelloggs, but now has come from NBC show "The Biggest Loser")

GNU Webster's 1913

1. n. One who loses.
2. n. A person who is habitually unsuccessful at some endeavor, such as employment or personal relationships.
3. n. A plan or strategy unlikely to succeed.

WordNet 3.0

1. n. a gambler who loses a bet
2. n. a contestant who loses the contest
3. n. a person with a record of failing; someone who loses consistently